[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-rt-users
Subject:    Re: 3.10.9-rt5 with Atmel AT91SAM9G25 SoC triggers "Trying to free already-free IRQ 1"
From:       Sami_Pietikäinen <Sami.Pietikainen () wapice ! com>
Date:       2013-08-30 11:18:19
Message-ID: EBD2DE4ADA47B94E831AED12A4B0CADA67E950BA () edb1 ! wapice ! localdomain
[Download RAW message or body]

Hello Michael

We have encountered the same warnings with the Atmel SAMA5D35 processor when using \
the RT_PREEMPT patch. We get the same warnings with both 3.6.9-rt21 and 3.10.9-rt5 \
kernels. However, the 3.6.9-rt21 kernel boots just fine, and we also had problems \
booting the 3.10.9-rt5 kernel. Therefore these warnings and boot hanging might be \
unrelated.

What's causing these warnings is still unknown, but at least we got the 3.10.9-rt5 \
kernel to boot. The boot problem seems to be caused by the TCB clock source \
(tcb_clksrc). You could try to unset the CONFIG_ATMEL_TCB_CLKSRC option, but this is \
not optimal configuration for rt. 

I have attached a patch which goes on top of the rt5 patch that seems to fix the boot \
hang issue. Could you please report the results if you have time to test this patch? \
Please note that I have not yet done any rt-tests with this patch.

BR,
Sami Pietikäinen
Software Developer
Wapice Ltd.

--- a/drivers/clocksource/tcb_clksrc.c	2013-08-29 16:14:14.611335823 +0300
+++ b/drivers/clocksource/tcb_clksrc.c	2013-08-29 16:16:28.129657272 +0300
@@ -192,9 +192,13 @@
 	clkevt.clk = t2_clk;
 	tc_irqaction.dev_id = &clkevt;
 
-	timer_clock = clk32k_divisor_idx;
+	timer_clock = divisor_idx;
 
-	clkevt.clkevt.cpumask = cpumask_of(0);
+	if (!divisor)
+		clkevt.freq = 32768;
+	else
+		clkevt.freq = clk_get_rate(t2_clk)/divisor;
+	clkevt.clkevt.cpumask = cpumask_of(0);
 
 	clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
--
To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[prev in list] [next in list] [prev in thread] [next in thread]